The BioWare Social Network shares details on a playable demo for Mass Effect 3 expected in January 2012 to offer samples of single-player and multiplayer play in BioWare's action/RPG sequel to owners of an online pass for Battlefield 3 (thanks GameSpot). They also announce that over the next couple of months they will reveal a way to get access to this demo with no purchase required:

Hello everyone! It's going to be a Happy New Year! Mass Effect 3 will have a pre-release demo in January 2012. This demo will have both single player and multiplayer sections, giving fans a taste of what's to come on March 6, 2012. Be first to the front lines in the multiplayer section of the Mass Effect 3 demo! Redemption of the Online Pass for Battlefield 3 will unlock this early access. But rallying for war is just getting started - in late November / early December, BioWare will announce other ways for fans to engage the enemy with their friends online from day one!

How can I get early access to the multi-player portion of the Mass Effect 3 demo coming in January 2012?

Owners of Battlefield 3, on any platform, who activate their Online Pass will automatically be granted early access to the multiplayer portion of the Mass Effect 3 demo. There is no need to enter any other codes, the early access will be applied to the EA Account associated with the Online Pass. Note: BF3 Origin Customers automatically have the BF3 Online Pass.

This applies to all regions where the demo is released (to be announced)

The exact date of the demo launch will be announced in late November

There will be another program whereby players and fans of the Mass Effect franchise can unlock this early access (with no purchase necessary) – this will also be announced in late November or early December.

There will also be a tool posted on www.masseffect.com allowing players to check if their EA account has been granted the early access.

The length of the early access period is TBA.

The single-player section of the demo will be available to all players on day one of the demo launch.